RF Shorts for June 12, 2014
A review of RF-related news during the past week.
June 12, 2014
Eutelsat blames Ethiopia for Satellite Interference
Peter B. de Selding reports Eutelsat Blames Ethiopia as Jamming Incidents Triple
in his article on SpaceNews.com. "Satellite fleet operator Eutelsat said intentional interference, which accounted for just five percent of the disruptions to its fleet in 2010, was responsible for 15 percent of the signal disruptions in 2013."
Eutelsat reported that it geo-located the uplinks jamming the satellites to northeast Ethiopia.
Saudi Arabia-based Arabsat's satellites have also been jammed.
Jamming satellites isn't difficult if you have an uplink with enough power to drop the signal-to-noise ratio of the desired signal on the targeted transponder below the level at which a receiver can decode. The higher-order modulation used to increase data rates is more susceptible to interference.
Peter B. de Selding describes how protest over the jamming will end up at the ITU, but says that "industry officials admit the United Nations affiliate has no real power to impose penalties on governments, even those that are identified as conducting or sanctioning the interruption of satellite signals."
Eutelsat is pushing an ITU proposal to use a global network of antennas to speed up geo-locating of jamming sources.
The targeted Eutelsat satellites carry a program from Oromia Media Network
of Minneapolis. Arabsat doesn't carry Oromia Media Network now, but de Selding says one industry official "speculated that the jammers may soon sign a contract that would put Oromia on an Arabsat satellite at 26 degrees east.
See de Selding's article for the steps satellite operators are taking together to track down jammers.
African TV White Space Put Under Microscope
I've previously reported on TV band white space initiatives in Africa. Russell Southwood describes the state of the initiative and future efforts in his article TV white spaces no Holy Grail for Africa: critics
. There are trials going on in Africa, with Nigeria planning to issue several licenses to trial TVWS participants.
Southwood observed that at a session on TV White Space at the African Telecommunications Union Digital Migration Summit last week in Nairobi, the issue was quite polarized with one faction stating that it was a good way to extend the reach of high-speed Internet connectivity and the other side stating that
it was not a good technology for the nation and didn’t live up to promises.
Southwood writes: "In a session in which the 'antis' seemed to throw every argument but 'the kitchen sink' at the idea of TVWS, it is perhaps fairest to summarize some of the main ones."
See his article for the complete list of arguments against the technology.
Comments and RF related news items are welcome. Email me at firstname.lastname@example.org.